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National Museum of Nuclear Science & History

Benjamin Bederson’s Interview

Benjamin Bederson, a New York native, was selected to serve in the Special Engineering Detachment during the Manhattan Project. A physicist, he was first sent to Oak Ridge, and then to Los Alamos, where he worked for Donald Hornig on designing the ignition switches for the implosion bomb. At Los Alamos, he knew Ted Hall and David Greenglass, who were secretly sending atomic bomb secrets to the USSR. Bederson instructed the 509th Composite Group at Wendover and was sent to Tinian to help wire the switches for the bomb. He recalls the feeling of expectation just before the bombing of Hiroshima and his jubilation at Japan’s surrender.

Date of Interview:
November 18, 2011
Location of the Interview:


Benjamin Bederson: I’m Benjamin Bederson.

Cindy Kelly: Can you spell it?

Bederson: B-E-D-E-R-S-O-N. Sometimes it’s called “Bederson.” I say Bederson. 

Kelly: And what was your birth date?

Bederson: I was born November 15, 1921. I’m about to have my 90th birthday next month.

Kelly: You are phenomenal. This man looks like he’s sixty-five.

Bederson: I like to say I’m on a plateau. But you know what a plateau is? A plateau is a flat surface but it has precipices on all sides. So I got to stay away from the precipices. That’s part of my job. It’s like Los Alamos–a perfect plateau.

Kelly: Well why don’t you tell us something about your background–where you were born, your education.

Bederson: My parents, who are Russian Jewish immigrants, who came to America—one just before World War I, and one just after World War I. They met at night school, a very romantic setting. They met at night school, and they lived in the Lower East Side. They were very poor. My father worked as a restaurant worker all of his life. 

I grew up mainly in the Bronx, and partly in Brighton Beach in Brooklyn. I would say one of the great things about New York is the fact that it had City College. And City College was—just as with many other people—was a defining event in my life, because it gave me a completely free education in exactly the subject that I wanted, which was physics. That’s basically my early background.

We were raised—not insignificantly—my parents were Leftists as were most everybody I knew in the Bronx. We lived in a sort of almost a communist neighborhood. I was brought up in my early days as a Young Pioneer of America, which was the communist equivalent of the Boy Scouts. So until I was in City College for a year or two, I would say that I was pretty radical. It slowly changed. My radicalism slowly changed. I became much more interested in science and physics. I gradually lost complete interest in being radical and ended up being hostile to the whole idea by the time I had left City College, which was fortunate, because otherwise I never would have lasted at Los Alamos. 

After two and a half years at City College, I decided to take a job for the Signal Corps. I moved to Philadelphia, from where I was drafted in 1942. For the next year and a half or so, I moved around. I had almost no basic training; was shipped immediately to Radio School to become a tail gunner on a B-17. That was the intent of my Army career: a tail gunner on a B-17; not a long-life expectant job in the Air Force. But I also had become a radio operator. I went to Radio Operator School in Chicago, but they kept me there as an instructor. 

From there, I went to a new Army program called “Army Specialized Training Program.” I took a course in electrical engineering at Ohio state university. In late 1943 during the Battle of the Bulge [misspoke: The Battle of the Bulge took place in 1944-45], and fighting was fierce in Europe, the Army decided to give up on educating its draftees and shipping them off to battle, to combat. 

Once again, by accident, there was an interviewing board that came to Ohio State. My commanding officer told me it was for something called the Manhattan Project, and said, knowing that I loved New York, said, “Here is a good opportunity for you to get back to New York.” I grabbed the opportunity, was interviewed. They asked me some strange questions about science and my career. The next thing I knew I was on a train going to Knoxville, Tennessee, from which I shipped nearby to a town called Oak Ridge, Tennessee, and that is how I got into the Manhattan Project. 

Kelly: So, what was the Special Engineering Detachment?

Bederson: The Special Engineering Detachment—it was already clear that a major effort was going to be made to develop the atomic bomb. By that time, 1942, 1943, already many famous scientists were being assembled at Los Alamos and elsewhere. And lo and behold, they discovered, just like physics professors in universities discover, you can’t do anything without assistants. So, they realized that they needed an infrastructure of machinists and engineers, and young budding scientists to assist in the development of the bomb. So they developed something called the Special Engineering Detachment. And they went around the country interviewing people who they thought might fit into the project. And sure enough at Los Alamos, there were many, many hundreds, almost a thousand, SEDs eventually ended up there. Some of them, like me, you might call budding graduate students. Even though I had only had two and a half years of college at the time. Many—also others were machinist and engineers. 

So, the SED, among other things, became a breeding ground. I guess it started at the war, and maybe they don’t understand it as much as they should, that this was a breeding ground for many physicists and chemists, and other scientists who after the war went on to have great careers in science, partly because of the start that they got in the Manhattan Project. That was a really unintended consequence of the Manhattan Project. I am an example. Well, of course I wanted to be a physicist before I got into the Manhattan Project. The experience I got at Los Alamos was invaluable. It helped me build a career. 

When I got to Oak Ridge, the first thing I noticed is that my feet were almost ankle deep in mud. It was a muddy place, and mud had this characteristic orange/red color, that you really knew you were somewhere in the mountains of Tennessee. Now Oak Ridge was really thriving. There were construction machines everywhere. There was activity everywhere. There was clearly something going on, and as I say in my memoir, the most interesting things that I saw were these huge buildings with towers that looked just like distillation plants. They were all over the place. My first impression of them was, that they are distilling sour mash whiskey to drop on the Germans and get them—to disable them. Now I realize that couldn’t possibly be true, and it was only of course many months later that I found out that the real purpose of the distillation plants was to distill U-235 from the principal isotope of uranium, U-238. 

We were housed in barracks, of course, like soldiers always are, but the barracks were cleaned by local young girls. So, again, it was very clear to me that this was something going on that was very unusual, but of course, we had no idea what it was. Also some of the buddies that showed up with me, they were all science majors from various colleges all over the country. So, I knew it had something to do with science; that was clear, but what it was, of course I did not know. 

At Oak Ridge, we were given tests. I was there for about a week, and they were trying to find out where I would fit in the Manhattan Project. Some of the people, particularly the chemists, stayed at Oak Ridge. The physicists types tended to go to Los Alamos. So, what happened was, I finally got shipping orders to go to Los Alamos along with several of my friends who were also physics majors. So, we just traveled in civilian trains, which was the first time I had used a civilian train since I was in the Army, and ended up in Lamy, New Mexico, which is the place people go to when they want to get to Santa Fe. 

Kelly: Describe Lamy. 

Bederson: Lamy was just a junction, as far as I could tell. It was on the Atchison, Topeka to Santa Fe, even though apparently the train never gets to Santa Fe, even today doesn’t get to Santa Fe. It was simply a junction on the railroad line. It was a one-horse town. That’s it. Now I was met there by an Army sedan, driven by a WAC, a lady soldier, who drove me to Santa Fe, drove me to the central square in Santa Fe, the Plaza. And let me off in front of this famous building 109 and it was just a storefront. 

I went in and I got my papers, and I handed it to a lady. I said, “Here I am.” I guess that is the same as what happened to everybody who came to Los Alamos. I handed her them. 

She looked at them. She said, “Fine.” She said, “Sit here; sit down. We’ll be with you in a little while.” I waited for about a half an hour and—just sitting in the storefront. The lady that I spoke to was Dorothy McKibbin. She was very nice and tried to make me feel comfortable. Of course I had no clue of what was going on. I had no clue of where I was going to end up. 

She just chatted and made me feel comfortable, and finally introduced me to a WAC. We got into a car. I believe, I can’t really remember exactly, but I believe that I was the only one in the car besides the driver. This was another one of these olive drab Army sedans. So that was my experience in Santa Fe. 

Of course, later on I found out that this was exactly the place where all of the famous physicists and scientists came and were greeted the same way by Dorothy McKibbin, and ended up at Los Alamos the same way I did. I probably was the lowest ranking scientist in the entire project, but I was treated pretty well nevertheless. 

I should say that it got pretty scary, because after we drove for a while, we started driving up the side of a cliff and it was just a road with no guardrails. We drove along this cliff, up and up and up until finally we reached the plateau which was the mesa in which Los Alamos was planted, but it was pretty scary, but we finally got there and past a bunch of guards. I reported to somebody. I don’t remember to whom I reported, but they shipped me to—they sent me to a barracks, and I put my gear in the barracks and I believe I went to sleep. 

Kelly: Tell us about your roommates that you recall living in the barracks with you. 

Bederson: Yes, the barracks were a very typical Army barracks. I said in my memoir that there were fifty soldiers. I think Val Fitch said there were sixty. I am not sure who is right. I do know that there were three coal stoves in it, strategically placed in the barracks to keep us from freezing. The beds were double bunks lined in a row, in two rows actually with the coal stoves in between. So there may have been fifteen bunks on each side, and I took a bunk just at random and stayed there for a couple of days, until finally somebody came up to me and introduced themselves as a friend of a friend. That was William Spindel. He was from Brooklyn. He had a similar background to mine and knew some people I knew. So we decided to become bunkmates. So, we shared a double bunk for the entire time I was at Los Alamos, almost two years. 

I don’t know exactly why, but I got the bottom bunk. I can’t remember. That was considered to be quite a coup, to get the bottom bunk. Next to us there were also two New Yorkers, and since the soldiers were from all over the country, it was very enjoyable to have New Yorkers next to us. One was a machinist—no, in fact, they were both machinists. They came from the Lower East Side. It turned out later that one of them happened to be David Greenglass. So, he was in a lower bunk too, so we were next to each other in these barracks in lower bunks. Then throughout the barracks were many of my friends. There was Norman Greenspan, who became a very good friend of mine, a mathematician trained in mathematics at Brooklyn College. Unfortunately, he died recently. 

Later there was Richard Bellman who became a famous mathematician and system analyst working for the Rand Corporation. He’s a legend there now. He also died some years ago. There was Peter Lax, who became a very highly distinguished mathematician working at the Courant Institute in New York. There was Murray Peshkin, who ended up at the Argonne; Val Fitch who won a Nobel Prize. So these were all my buddies in the Army, some buddies, really strange set of buddies. 

I should mention one person in particular who I later became very good friends with. That was Richard Davisson. Richard Davisson was unique at Los Alamos, I am sure unique in the world. He became a legend when he ended up at the University of Washington. He became famous after the war at the University of Washington, because he never finished his PhD as far as I know, but nevertheless, he was an invaluable member of the Physics Department, because he was so smart. He happened to be the son of Davisson-Germer fame, who won the Nobel Prize for discovering the wave-like nature of the electron. So, he was the son of a Nobel Prize winner. 

He and I spent a lot of our time trying to avoid Army duties and saluting. We hated saluting. It just didn’t make any sense. Here we were working on this fantastic project. We still had to salute. We still had to go in formation. We still had to undergo Saturday morning inspection; things of that sort. His way of dealing with it was, he made his bed and he never slept in it. He slept on top of his bed for the entire two years that he was at Los Alamos. He was able to brag that he never made his bed in the Army. Anyway, Dick Davisson, unfortunately also passed away. He was an unusually brilliant special guy, a friend of mine. Of course, people like that I never would have met in the regular Army, if I had ended up as a tail gunner. 

Shortly after I arrived there, they assigned me to a project. The project was called Jumbo. I found—it was a huge container, steel container, huge in size. I don’t know, fifteen or twenty feet high, maybe eight or ten feet in diameter. I was assigned—SEDs always had senior scientists—that is, the science SEDs always were assigned to some project. There were of course, always very senior physicists and chemists who they worked with.

The particular person I was assigned to was Philip B. Moon, who was British. He had apparently arrived at Los Alamos at almost the same time that I did. So we came there together. His assignment, and therefore my assignment, was to study the ability of Jumbo to contain a abortive atomic bomb. If the atomic bomb did not actually work properly, the radioactive material would have spilled all over the landscape. It would have been a disaster of enormous proportions. So the idea was to put the bomb inside this container. If it fizzled, then the container would hold it and keep it from spreading around and destroying Los Alamos essentially. If it worked, then it didn’t matter, because it would vaporize the container. So that was what was called Jumbo. 

Our job—he had had some experience. I should say a few words about the British. The British, of course, were also working on an atomic bomb. Sometime in late 1942, their project, which was called the Maudd Project, I’m sure you know about that. The Maud Project by arrangement through Winston Churchill decided to join forces with the Americans. So, the British were shipped to Los Alamos as a group. There were maybe six or eight of the famous—of scientists. There were all of the most famous physicists in England at the time, including Oliphant. I have a list here; just a minute, let me read them for you: George Thomson, Marcus Oliphant, James Chadwick, John Cockcroft, Philip Moon, and P. B. Blackett. 

Now it turned out, P. B. Moon—I am slightly mistaken in my memoir—P. B. Moon was a student of Rutherford’s, not Chadwick. He did his work at the Cavendish Lab at Cambridge. He worked with Rutherford, and then ended up at Birmingham with Marcus Oliphant, who is another nuclear physicist. So he was part of this Maud group, and he was assigned Jumbo too, just like I was, but I worked for him. 

So, I started my actual research. My research consisted of blowing up containers to see how strong they were. I became the expert in explosives. For two reasons, we didn’t do the work actually on the Los Alamos mesa. The first reason was, they did not want us blowing up anything at Los Alamos, because it was pretty dangerous. The second reason was that it was too disruptive. There are too many wires and pulses, and electrical sparks all over the place. So we were really destroying some delicate work going on at Los Alamos. So they put us away in a second mesa called Two-Mile Mesa. So, I worked at Two-Mile Mesa with Phillip Moon and with another one or two other SEDs, blowing up things. We used what are called strain gauges to study the actual distortion of the metal by the explosives. We would install small explosives inside small containers, put strain gauges on the outside of the containers, blow them up, and measure the distortion of the steel by the explosions. 

I was not given the job of actually deciding how strong these were. I assumed that Philip Moon was doing that. I was giving him the data. So I was basically his hands, along with another friend, another SED who incidentally actually did have an accident right next to me. He blew up one of these explosive caps by accident. He was badly injured by that, but he recovered. So we worked on that. 

Now, I should have mentioned that I was not allowed to work in the main part of Los Alamos called the Tech Area, because I had not been cleared yet. So, I was given sort of a second-class clearance, a tentative badge called a blue badge. I did not know at the time that they were investigating me back in New York. While they went through this series of clearance in New York City, apparently I passed, and was given a white badge which was an entree into the actual Technical Area at Los Alamos where all of the important work was going on. So at that point—that was two or three months after I started on Jumbo—I got the white badge. Just at that time, they decided to forget about Jumbo, because by that time their confidence was such that they were pretty sure that the bomb would work. They decided that Jumbo was a waste of time. Jumbo’s still there.

Kelly: It’s at Trinity. 

Bederson: Are they gonna keep it there? Have you been inside? That’s wonderful. Of course, I never saw it there. I saw pictures of it. All I knew is that I was blowing up little models of it. So, that’s the end of my Jumbo adventure.

Kelly: That’s interesting because we found out on Two Mile Mesa, little tiny Jumbos and we wondered what they were. 

Bederson: That was me. So, both Moon and I were reassigned. However, we remained good friends. I loved the guy. He was numerously entertaining and very highly cultured, very British, had a British wife. The two of them had Arthur Rank movies that they used to watch. I used to love the two of them very much. We remained in touch for a number of years after the war. 

Kelly: So let’s see, after the work with him—maybe you can tell us about the Mushroom Society.

Bederson: Oh, that was a little later. 

Kelly: What was next?

Bederson: What was next is, I got a new assignment. The new assignment, I met my boss, my new boss, Donald Hornig, H-O-R-N-I-G. Donald Hornig is a famous professor and I think he is still alive. He is hitting a hundred, almost hitting a hundred. No, he was only maybe two years older than me. So he is still in his mid-nineties. He is in his nineties now. He is a professor of chemistry, or was a professor of chemistry, at Princeton University. Long after the war, he became a science adviser to Lyndon B. Johnson. When I knew him, his assignment at Los Alamos was to design the ignition switches which operated the explosives, which in turn operated the explosive lenses, which caused an implosion. So, you have switches. You have the igniters on top of the cones of the explosive lenses. Then you have the implosion. So our job was, at the beginning, to get switches. 

Now the important thing to note is that the bomb consisted of—it was spherical and the whole purpose of the implosion was to compress the plutonium, the plutonium metal, so that its density causes it to become critical and to cause a nuclear chain reaction. In order to cause this explosion, to cause an implosion, you need to have the entire sphere compress at the same time. If like say the left side explodes before the right side, then you will get a jet and a stream, and it will abort. So you need to know that these lenses ignited at precisely the same time. There were thirty-two such lens around the sphere. Each of these thirty-two lenses had an explosive igniter on the top. Then were thirty-two switches somewhere else. The thirty-two switches were what Hornig and I did and what I was supposed to help him with—to get these thirty-two switches to ignite at precisely the same time. 

Well, that is not a trivial thing to do. The requirements on timing were microseconds. That is to say, these switches need to close within a few microseconds of each other. In 1944 when I was doing this, a microsecond was a very short time. It’s not a short time anymore. Everybody who uses computers, they work in much shorter times these days, but in those days, a microsecond was a very short time. And so we had to develop the switches, and then we had to test them to make sure that they were igniting within a few microseconds of each other. So that is what we did. We had a laboratory. We didn’t have the switches, because the switches had not been designed yet, but we had to devise the testing system so that we could test the switches when they were designed.  

So Hornig, what he did was he figured out how to test these switches to within a microsecond of each other. Now I am not sure that I got this exactly right, but I think that what he did was he remembered that Michelson at Cal Tech had a streak camera to measure the speed of light. That was a pretty good way to start, because we know the speed of light is very high; therefore if you are making measurements, the measurements of the speed of light have to be precise within a very short time. So he got that, he actually got that camera or something like that. I think it was the same camera. He got it and brought it to Los Alamos and he gave it to me. He was like, “Here is your camera; go do it!” 

So, the camera was conceptually very simple. It was just a rotating, six-sided mirror, which was rotated by a stream of air going on it with the propellers. It went very fast, and light would come in on the mirrors and the light would be scattered by the mirrors along an arc like this. Then there would be a film that was maybe five feet in length that would be stretched along this circle. And then the signal from the light would hit somewhere—you wouldn’t know where, but one of the sides of the mirror would surely hit the film somewhere along the five feet of length. 

So what we would do is we would line up—I’ll tell you about the switches in a minute. We would line up eight switches. We would ignite them. The light from the sparks would hit a bunch of lenses and would go to the camera. The spinning wheel—we would scatter the light around the film, and then I would take the film, go to the dark room, develop it and look and see how simultaneous the eight sparks were of these switches. 

The sparks, that was interesting. The sparks that were developed by—I forget exactly who. It was me with Margaret Ramsey, my coworker at the laboratory back in the lab. It was just simply two pins, two regular ordinary pins, like this, and the spark would go between the pins. That is all. It was just a markup for the real switches that were going to occur later. 

So, that was my job. My job was to put in all the wiring and to expose the film, and then to run to the dark room and to develop in the dark room, and then I would show the final result to Donald Hornig. He would decide how good these switches were, or how good the switches would be and then make recommendations from that. So that was my job. It was an interesting job. It involved a lot of physics and for a kid with only two and half years of college, I was really thrilled with the idea of being able—I was working in a laboratory doing real science. It was really a wonderful experience. 

Kelly: Interesting. Can you tell me about—since there were not that many women scientists, can you give us a little introduction to Margaret? 

Bederson: Well, Margaret Ramsey was a chemist. She had her degree. She had a Bachelor degree from chemistry, from Boston. I forget what college, but she’s from Boston. We worked together as a team. We wired these little pins, and we soldered them with plastics. We made little forms to press them together. So, we worked together very happily for—I forget, it must have been four or five months. Margaret was a really fine scientist, and she was the first person that I had ever worked with as a colleague. She ended up marrying James Keck, another SED. They still live up in the Boston area. James Keck—he was another fine fellow and the two of them married and have been married over since.

Kelly: That’s great. So, when did you work for George Kistiakowsky?

Bederson: While I was still on Jumbo, they did not let me know anything, but I got my white badge. And shortly thereafter—it could not have been more than a week or two—I was told that we were going to have a little meeting with the head of what was called the Explosive Division, of which I was now part of, because Donald Hornig worked for Kistiakowsky, who was the head of the division. 

So, Kistiakowsky was Hornig’s boss, and so I heard that there was a meeting. I was invited to the meeting, and there were like maybe half a dozen SEDs and a couple of civilians. Kistiakowsky came to the office, and since I had my white badge, I was cleared. It was perfectly legitimate to get the information, and he simply told us what we were doing. That was probably three months after I got to Los Alamos, two or three months after. He told us—that was a memorable moment in my life, of course, because he laid out the whole history of the atomic bomb, of nuclear fission, and the entire history of the Manhattan Project and of the entire goal of the Los Alamos.  

He told it to us, and you have to understand. I know people have mixed feelings about the use of the atomic bomb. Many people do not feel very kindly about the use of the atomic bomb. You have to understand where and when this was, and where I came from. I came from a Jewish family. My Jewish relatives in Russia were being killed left and right. I knew about that already. The world in 1944 was a horrible place. There were thousands of Americans being killed every day. The only thing we could think of was the war and to end the war as soon as possible, to end the killing in both Europe and the Far East. When I heard that we were working on something to end the war, I could not have—it was really hard to describe how I felt, how happy and thrilled and honored I was to be working on something to end the war. I knew it would end the war. We all knew it would end the war if it worked. The way history works: history never follows your script. So, sure enough the war in Europe ended before the atomic bomb was actually implemented, but it did play a role in ending the war in Japan. 

Kelly: Can you give the name George Kistiakowsky and just describe him?

Bederson: So George Kistiakowsky—you have to understand that I have a Russian background and I think he was bald and a thin aesthetic looking man. He started speaking with a heavy accent. I thought, “My God, what is he doing here?” Little did I know he was a professor of chemistry at Harvard University. He was so honest and so giving that it’s hard to describe. He just simply laid it out. I don’t know whether he was authorized to do all that. We’d hear all these stories about need to know and about how everything at Los Alamos was compartmentalized—that was nonsense! Within three months of my getting my clearance as a PFC [private first class] at the time, I was told this immense secret without any hesitation by Professor Kistiakowsky. Of course, I could never forget the feeling. But, he was a very interesting guy. He certainly put it across to these low level individuals that he spoke to. 

Kelly: Why don’t you talk about being invited into the Tuesday—?

Bederson: Once I got into the Tech Area, you have to show your white badge to get in. By today’s criteria, it wasn’t very much. It was just a white badge. Anybody could have made it. Anyway, I guess people didn’t think of those kinds of subtleties those days. I got into the Tech Area, guarded by MPs, and I immediately found out that there were these Tuesday evening seminars that met in the hall within the Tech Area. Of course, I went to them, why wouldn’t I go? 

The first one I went to, there was this physicist named Enrico Fermi gave a talk. I listened to this talk, and here I was just thinking about the atomic bomb, and believe it or not, he didn’t talk about the atomic bomb. He talked about the hydrogen bomb. It was really mind boggling. Here he was—it must have been in the spring of 1944. Yes, 1944, and here he was talking about a bomb whose predecessor had not yet been built. But the idea of nuclear fusion was on his mind, and he was thinking ahead. He had already realized that nuclear fission was going to work, and it would somehow or another produce an atomic weapon. Then he realized that using the fission bombs, you can actually create a temperature high enough to cause nuclear fusion, cause deuterium to fuse to form helium the way the sun does it. 

So, he was thinking about a means of producing a controlled and uncontrolled reaction with a fusion reaction of deuterium into helium. This was really 1944. He was also a very interesting guy. He had an Italian accent, not a Russian accent, not a British accent. He had an Italian accent. I told you the international nature of this. The good fortune of America in getting these notable scientists away from Hitler and getting them into the United States, and we got Enrico Fermi. I mean, Hitler could not have been dumber to let people like Fermi go. Not that he would have worked for Hitler. He hated Hitler anyway. 

So he came here with this Italian accent. And the Italians I knew, and I knew plenty of Italians from the Bronx, and they all had the same accent, but they were not physicists. They were storekeepers. Here he was, this famous physicist giving this lecture, and it was quite an experience. Then later on I heard many of the other notables give lectures there too, including Niels Bohr. 

Kelly: It must have been fun.

Bederson: To tell you the truth, I had mixed feelings. It was fun. The daylight time was good. The army part—I have to admit—I didn’t like it. I didn’t like sleeping with fifty or sixty men, all snoring, having a single bathroom with no booths, just a line up of toilets. It was undignified. 

Kelly: Everybody’s interested in spies. One of the things you noted in your memoirs—

David Greenglass was very political and we used—he was in the bed next to us. Here he was talking about Russia and how wonderful Russia was and all that. He really was a communist; quite interesting. It had even crossed my mind—I have to honestly say this. It crossed my mind that there was something wrong with a communist being at this project. Russia was an ally and the war in Russia was going on very heavily, but it didn’t seem right, but I certainly never did anything about it. It crossed my mind, but I didn’t do anything. It was so bad that eventually Bill Spindel and I got permission to move out. And Greenglass and his bunkmates stayed where they were, but we remained sort of friendly. 

He was a communist. I don’t even think he would deny it if you asked him.

Kelly: So, he was comfortable sharing his views 

Bederson: Yes, there were never any constraints about that.

We never talked about work, except although I noticed that—I did read the testimony during the trial, during the Greenglass trial. I did read the testimony and he did mention my name in the trial. He said that he had once asked me, innocently—he was actually machining the parts for the bomb. He was machining lens molds. He asked me—he says he asked me what they were for. He said that I said something about a bomb, but I don’t think—I don’t remember that. He did get me into a heap of trouble, because he said that I was a friend of his. The FBI actually called me in and we had a couple of sessions, and it all worked out fine. The FBI— despite what you may hear about it—They were very fair. They listened. They asked hard questions, and it turned out that I was an innocent victim, just as many other people were of his friendship. 

Kelly: Tell me about Ted Hall.

Bederson: Yes, now Ted Hall was another one, another SED. He was a very young one, right, nineteen. For some reason or another, I met Ted Hall, and he got interested in me, because of my friend Norman Greenspan and I loved Gustav Mahler. Still do. I just heard the Philharmonic only last week play Mahler’s Second Symphony. Greenglass, who was an electronics expert, had constructed an amplifier using parts from the electronic storeroom at Los Alamos. He built an amplifier. It was a really good amplifier. We had a speaker somewhere. We placed it in Richard Bellman’s office. He had an office. Of course, he was a theorist. Experimentalists did not have offices, but he had an office, because he was a theorist. 

We had the amplifier, the large speaker and a record player set up in Richard Bellman’s office. Norman Greenspan and I decided to form a society where we could listen to classical music. We called it the Mushroom Society, because we could only meet at night when there was nobody there. We would play music very loud, Mahler and Beethoven, Wagner, and all of the classics very late at night, and really enjoying it. Ted Hall heard about it, I guess. He invited himself to become a member. So we were glad to have him as a member and he would come to hear the classical music. He became a member of the Mushroom Society. That is how I knew Ted Hall. I did not know him outside of the Mushroom Society. We didn’t really talk much, because he was a very taciturn person; never really spoke much at all. We also invited Phil Moon and his wife to our concerts. That was quite interesting. The room could not have been more than seven feet square. The three of us, plus Professor and Mrs. Moon listening to—I forget what we were listening to, but it was quite an experience. It was a little embarrassing but nevertheless, it was great. 

Kelly: Klaus Fuchs—did you know him?

Bederson: No, I didn’t know him, but I knew enough—

Kelly: Yes, that’s quite a lot. One thing that I thought was very charming was when you forgot to remove the shutter. 

Bederson: We had the final test when these markup switches were going to be—no, I’m sorry, they were not the markups. They were the real switches. The real switches had arrived. They were really kind of bulky, and they were nothing like the little pins we were using, but they were professionally manufactured, and we had them lined up. Donald Hornig was there, because it was a very important test. We lined them up. It took me probably five hours to wire everything up properly. It was probably three o’clock in the morning when the thing went off and I threw the switch. 

The thing went off, and Don Hornig said to me, “Wouldn’t it be funny if you forgot to remove the shutter.” It was very much like any big camera. It had a shutter in front of the film, only the shutter was five feet long too. You had to pull it all the way out. He said, “Wouldn’t it be funny if you had forgot to remove the shutter.” 

At that point, I realized I had forgotten to remove the shutter. So I almost crawled away. I told him, “I forgot to remove the shutter,” and he laughed, because I am sure it does happen to everybody. 

He was very reassuring and said, “Well, we can do it over again.” So, we did it again the next night. I will always have a very soft spot in my heart for Don Hornig for having not killed me for having ruined the first experiment, but it turned out okay only a day later. 

Can you imagine laughing at that? If a graduate student of mine had done that, I’m not sure that I would have been so forgiving. 

Kelly: Let’s go to Wendover. What was that like? What was the role of the 509th?

Bederson: Wendover of course was the staging airfield for the 509th Bombardment Squadron. That was to drop the bomb. A few of the people from Los Alamos were told to work with the bomb crews to show them how to throw the switches and how, in general, to prepare to trigger the bomb. You can be sure the bomb was not armed while they were not over a target. I was one of the people who was chosen to instruct them on how to throw the switches and arm it. I was only a PFC at the time and they were all captains, lieutenants, corporals, and majors. I was supposed to instruct them. You know the Army is a very hierarchical organization. You cannot have a PFC or a corporal instructing a captain on how to do anything. So, they realized that would never do. 

So, some genius decided to make me a civilian artificially. They gave me two hundred dollars. That was an experience in itself. They said, “Go to Santa Fe and buy yourself some civilian clothes.” So, I went to Santa Fe, and sure enough, I bought some civilian clothes. I bought a sharp jacket, some pants, and shirts, and tie. I brought them back to the barracks. I wore them, and everybody was really thrilled to watch me. Everybody was making numerous jokes. 

But I could not buy shoes, because shoes were rationed. I only had Army shoes, which are inside out, so you see the rough parts of the shoe. They go up to the ankle. So I needed a shoe ration certificate. So, I actually had to go to the security officer and explain it to him. I had to get a note from my commanding officer, who—by the way, my commanding officer didn’t know anything about the atomic bomb. So they were all—there was always a certain tension among the SEDs’ atomic group, because we knew, and our bosses didn’t know, what we were doing. We felt very important. We were probably pretty snarky about it. They didn’t care for our attitude much, I’m sure. 

Anyway, I got written permission, which I have in my records here. I do have some records. I got written permission to—probably the only secret document in the army which permits a person to buy a pair of shoes. So I got permission and I bought a pair of civilian shoes. 

Then, I masqueraded as a civilian in my periodic trips to Wendover. We would go to Albuquerque, take a flight to Wendover. Fly over the desert. There, I would stay in a motel, as a civilian in a motel. That was really a luxury, a private room. So, I would work with them during the daytime and at night, it was right near Nevada. I would gamble at night in the gambling casinos, having a ball, playing blackjack. Then fly back. Change out of my civilian—into a lowly GI. I would become a GI for a while, and then the next time I would go as a civilian. So, it was really a schizophrenic life I was leading for a while there. 

Kelly: Can you describe your civilian jacket?

Bederson: Well, it was a very sharp jacket. I thought about that for a long time, and I said, “This is my only chance I am ever going to have to have a sharp jacket. I am not going to buy a conservative tweed jacket.” So, I bought a—now I can’t remember to this day whether it was blue or green. I think it was green—red or green. I think it was green. It may have been red, but it was a very sharp jacket, and that is what caused hilarity in the barracks. I realized there was no reason why I couldn’t do. Nobody could stop me. So, that was my way of showing my independence from the army. 

Kelly: Should we go to taking the Green Hornet?

Bederson: So, then it was clear that we were getting ready. Now I forget—I think that must have been probably June. You probably know better than I do. Late May or early June before Trinity, before Alamogordo in July, right, July 12th, 13th?

Kelly: Sixteenth. 

Bederson: Sixteenth, oh. So, I was given orders to go to Tinian, to go to the assembly place where the bomb was being assembled for the very reason that I knew how to wire the switches. So, along with a few dozen others, altogether probably forty or fifty took this military plane. It was not a very comfortable plane, very much like most military passenger planes called the Green Hornet. The Green Hornet flew me plus a civilian, Ed Stevenson, who was a professor at the University of Virginia, and a few others. 

We flew to LA and then to Hawaii. We stayed in Hawaii overnight and then flew to Johnson Island, and then finally to Guam, and then finally from Guam to Tinian. Guam and Tinian are a part of the Mariana group of islands, which were actually Japanese protectorates and were captured not very soon before that by the Americans, a few months. Tinian was converted into this airfield, which for a while was the largest airfield in the world. There were hundreds of bombers, B-29s, shuttling back and forth to Japan from there. 

That is where we set up shop. We set up shop in a Quonset hut. We had a living Quonset hut and a laboratory—a working Quonset hut. The civilians had another Quonset hut. The thing I loved about being overseas was that once you got away from the US, this artificial barrier between officers and enlisted men and civilians was completely gone. Civilians and officers were living exactly the way we were. That made me feel much better. I never really liked the idea that officers had better quarters than I did. 

Kelly: I’m interested in the books that you sent ahead, so you had something to do. 

Bederson: Here is my pocketbook of verse. This is the cover from the pocketbook of verse which I carried with me everywhere. I was standing in line much of my daylight hours as everybody else was standing in line. I would read poems from one poem to the next for months at a time. I learned to love some of these poems. This is the cover. It broke up. The original cover broke up early on, and I made an artificial cover. It says, “The pocketbook of verse, or whiling away the idle hours on Tinian.”

General Groves decided it was time to meet some of the GIs. You know in his autobiography, he never even mentions the SED. We were really invisible to many of the big brass. Anyway, he decided that it was time that he met some. So he called a few of us together. It was probably early December of 1945—1944. He gave us a lecture, but the lecture had nothing to do with atomic bombs. It was a lecture telling us to write home to our parents on Christmas because they need to hear from us, because they are very worried about us. So, please write home to your parents. 

Interestingly enough, looking at some of the information that I saw on Cindy Kelly’s website, the Atomic Heritage Foundation, I saw some sort of a note from somebody at Oak Ridge. He talked about having met General Groves. He mentioned that General Groves told him to be sure to write home to his parents. So, I realized that General Groves is going around all over the Manhattan Project sites telling all of the SEDs to write home to their parents. That was my interaction with General Groves. Since I was a good boy, I wrote home to my parents anyway. I didn’t need him to tell me that. 

One of the true ironies of history—who could have predicted that the island of Tinian was laid out like the island of Manhattan. The soldiers or the CBs who made the island. It was a flat island looking roughly something like Manhattan. So, they laid it out with the streets and avenues like 42nd Street and 5th Avenue, Broadway, 9th Avenue. So, Tinian was laid out like Manhattan. Think of this as the culmination of the Manhattan Project which nobody could have ever invented. It just happened by pure chance. Who would believe it? Unless there is some guiding light up there which really is telling us what to do. It makes you think about that. 

This Quonset hut—we had two resident Quonset huts, where we lived. Then, we had a laboratory hut which was air conditioned. It had a much fancier layout than the living quarters. It had a dark room because it was necessary to test the camera, which I should have mentioned of course was shipped over from Los Alamos, which we used to test the switches. 

I was in the Quonset hut when I was told Curtis LeMay was going to come and give us a visit, but I was dressed in my usual Tinian way. It was a very warm, humid climate. I had my Army shoes on, my boots, and a pair of shorts. And that’s all. I didn’t have a shirt. The people in charge there said that “this will not do” because Curtis LeMay—he’s a big shot general. He wouldn’t like to see a big shot general dressed like you are. So they said, “What are you going to do?” It was too late to bring me back to my barracks, to my Quonset hut, so they shoved me into the dark room, turned on the red light, which would inhibit him from coming in and they locked me in. I stayed there for about half an hour. They finally knocked on my door and said, “It’s okay now. He’s gone.” I went out and they were all buzzing, saying what a funny visit it was because they kept telling Curtis LeMay how important the bomb was and he was simply very skeptical about the whole thing because he had been sending hundreds of these incendiary missions over Tokyo and other cities. He’d been doing it day in, day out for months and to think that one bomb, one plane could do the work of his entire force was just too much for him to take. He just didn’t believe it. Later on he realized how important it was and when he became the strategic air command, he didn’t take that use of atom bombs off the table for use in a possible cold war. He was very much of a hawk all his life.

Kelly: Where were you and how did you learn of the dropping of the bomb?

Bederson: Well, the night before, which was August 5th, we knew the bomb was going to be dropped that night that they were going to take off that evening. So we sat—now, I wasn’t invited to see the takeoff. I didn’t ask to see the takeoff. I think by then I was beginning to feel a little funny about it. We just stayed in our barracks and we talked. The Navy photographers were there. There were photographers who were told to take pictures of the takeoff. There was William Laurence. He was the distinguished New York Times science writer. He was there and he was interviewing us about it. So we sort of—we knew that the secrecy was about to be lost. So we were a little more open than usual, talking, hinting about how important it was, but we could not of course say exactly what it was. We talked in sort of circles a little bit about what was going to happen. I went to bed. It must have been about one o’clock.

I woke up the next morning, and we have a radio. I turned on the radio, and that is when I heard about the bomb, because it had already been dropped. Announcers were already announcing it, and Los Alamos was already being spoken about. So the secret was out. Everything was done. Nagasaki [misspoke—Hiroshima] was devastated, destroyed. The world had changed while I slept that night in a Quonset hut in Tinian. The world—I knew it was going to change, and sure enough it changed. 

Of course, I forgot to mention that I kept a diary most of the time while I was there, because we all knew how important it was all along. I bought this stenographic notebook and I started writing in it the day I took off from Los Alamos. Let me see if I can find August 5th. I will just read the first paragraph from August 5th. I was sitting in my barracks that evening. I will just read what I said here. 

“There are eighteen canvas cots in our Quonset hut. Two of them are being temporarily occupied by Navy photographers, who have just flown from Guam to film our setup and to take off. The other sixteen supply the sleeping facilities for the entire enlisted men membership of the first technical service detachment. That is what it is called. Most of the fellows are gathered in one corner of the hut, and there is much excited talk. The Navy men are completely confused by the hints, and their wild speculations.” 

So I go on and on and on about that. Let’s see if I can find August 6th. I spend a lot of time about that. I talk about my job, about my ignition expert, the X-unit. I talk about the X-unit. Then after I got back to Los Alamos, I reread this, and I said, “My God! What have I said?” I realized that I might have said something that really I should not have said in my diary. 

So, I was a smoker at the time. You know, I was a two-pack a day smoker. Isn’t that amazing? So, what I did was, I destroyed the evidence. Just to make sure, I just got—the thing I said about the X-unit, I destroyed. I tried to make it look like an accident, but I don’t think it worked. So then my next entry was August 10th. In the days that followed we were so excited that I didn’t write. I don’t think I wrote for three and a half days.

And then on August 10th, I said:

“Today there are farmers in Wisconsin talking about atomic bombs over their dinner table. There must be countless street corner arguments about atomic bombs in every city in the country. People throughout the world must be feeling their soberest, matching their relation over this new, spectacular turn of the war with the tempering knowledge that this thing is bigger than it appears, and that though it will help end this war soonest it might very well mean other and more important things too. A few days ago the best kept secret of the war, it is now being more talked about and written about than even I thought it would be. It’s funny that all along I knew what this weapon meant. There is no overestimating its importance, yet I know that the news is out and I’m still amazed the treatment it’s getting.

“Though I know its destructive powers, I was still awe-stricken by the after photographs of Hiroshima. With the ‘Gadget’ there was no possibility of an anti-climax. We have argued about its effect and its importance, but the day after we dropped the first one, I divided my predicted duration of the war, which was one year originally, by two. I divided the quotient by two again the next day when Russia entered the war, and even that may be due to some extent to the ‘Gadget’—that is what we called the atomic bomb. So, now I say three months and I am a pessimist about these things. 

“Now we are listening to the hourly news broadcast and having a fine time separating the truth from the bunk. This was the one where some foul publicity searcher named Jacobson who none of us had heard of claimed a bombed area should remain uninhabitable for at least seventy years. That is not true. The days of—that is a half-truth and consequently difficult to deny.” 

I spent a lot of time in my diary after that writing about the consequence. I don’t think you want to read about my pontificating, about international control. I was thinking about how to control the bomb. I thought about and I said, “There is no other way. It has to be international, because sooner or later somebody else is going to get the bomb. Then what are you going to do? Then there will be two countries with the bomb. Then there might be four countries with the bomb. There is no end to it. How can you live with a world filled with atomic weapons? It has got to be under international control.” I said, “That is the only way you can have it.” 

Then at the end of my pontificating about this, I said, “And then I am probably all wet.” I was right. I was all wet. The bomb has proliferated. It is not under international control. Who knows if it ever will be? One doesn’t know. It is still with us, and it is a bigger threat than ever. Was it August 10 or 11 that the war ended?

Kelly: August 14.

Bederson: The armistice—when the armistice was announced—

Kelly: The fourteenth.

Bederson: That night [August 14] I got so excited. I said, “I gotta tell somebody.” I had heard about it. Of course I was listening to the radio. I went over to the officer’s tent, which was exactly the same as ours. There was Ed Stevenson asleep. I shook him and I woke him. I said, “Wake up, the war is over!” 

The interesting part of that is that that was an expression that in the Bronx we used all the time, especially when we were playing handball or we were playing stickball or whatever we were doing, and somebody would be half asleep. We would say, “Wake up, the war is over!” 

I said, “In my life, I am going to be able to use this expression once, and it will really mean the war is over.” 

And so, I woke up Ed Stevenson, and I said, “Wake up, the war is over!” That was a culmination of a long dream of mine. 

Kelly: What was his reaction?

Bederson: He was sort of drowsy. I think it took him a while to realize what had happened, and then of course, the aftermath. 

For many years at NYU, I taught a course called Physics in Society. It was probably an outgrowth of my experiences at Los Alamos and elsewhere. It addressed science-related societal issues. Of course one of the most important of the science-related societal issues was the atomic bomb. I would spend a part of the course talking about the atomic bomb. The students always raised the question of, “Did Truman make a mistake in dropping the atomic bomb?” Many students then and now think it was a mistake to drop the bomb. Many people think it was a mistake to drop the bomb. 

I did not think it was a mistake. I looked at the students—usually I would look at the students in the class, all of the young people that are nineteen, twenty, twenty-one years old, and I said, “You know, many of your parents would have been killed if there had been an invasion of Japan. And there would have been an invasion of Japan if the Japanese had not surrendered. And you would not be here.” Of course there is no way of knowing that, but you have to realize that dropping the bomb saved lives, saved American lives. It killed a lot of people, and you can never understand the horror of that. There is no doubt about that, but war is horrible, and the war was going on, and people were getting killed all the time. The Americans were getting killed, and I guess the first thought was to save American lives. It may have saved Japanese lives too. Who can tell how many Japanese lives would have been lost had there been an invasion of Japan? Probably a lot. 

So, I think that was an argument that was very telling and the students—many of the students understood that. It was a tough decision, but Truman made the right decision. Not many years after the atomic bomb was dropped, and many—a few years after there was a lot of testing of atomic weapons. The Russians had succeeded in developing an atomic bomb. The hydrogen bomb was successfully developed. The hydrogen bomb has a destructive power many, many times larger than the atomic bomb. Now the world is filled with hydrogen bombs in the Russian arsenal, the American arsenal, and who knows what other arsenals. The hydrogen bomb if dropped in Manhattan would destroy the entire city. It would destroy the entire island. That means that two or three million people would have been killed, and the entire culture of America would have been destroyed. It is unthinkable, and yet it could happen. 

I still think that what I wrote here is still true. The only way to solve this problem is to have an international control of atomic weapons and end their destruction. At some point in the distant future if we still exist, the world will come to its senses. We will form a truly well-policed, organized organization, part of the United Nations hopefully, and atomic weapons will be destroyed. I doubt I’ll live to see it. Maybe people in the audience will live to see it, but it’s worth looking forward to.

Copyright 2013 The Atomic Heritage Foundation. This transcript may not be quoted, reproduced, or redistributed in whole or in part by any means except with the written permission of the Atomic Heritage Foundation.